Gerard Ateshian's research combines theoretical, computational, and experimental methods to address the biomechanics of biological soft tissues and cells. His initial focus of research addressed the biomechanics of diarthrodial joints, including the measurement and analysis of their kinematics and contact mechanics, and the quantitative assessment of articular surface topgraphy and cartilage thickness. These studies were followed by the investigation of cartilage mechanics, with a focus on the disparity between the tensile and compressive properties of this tissue, and the pressurization of its interstitial fluid under loading. Direct measurements of this interstitial fluid pressure brough new insights and evidence with regard to cartilage lubrication, which became a major topic of investigation in the Musculoskeletal Biomechanics Laboratory.

Since 1996, Prof. Ateshian has established a close collaboration with Professor Clark T. Hung in the area of cartilage tissue engineering. This highly fruitful collaboration has led to important breakthroughs in this field, with notable advances in the understanding of the role of mechanical loading in engineered cartilage growth and development. This collaborative effort has also extended to the fields of solute transport in loaded tissues and tissue constructs, and cell mechanics, producing insights into the cell's mechano-electrochemical environment and its response to mechanical and osmotic loading.

Prof. Ateshian has also invested significant efforts in the modeling of biological tissues and cells using Mixture Theory. He has placed a particular effort in understanding the role of chemical reactions in mixtures, to address important challenges such as the modeling of tissue growth, and active transport processes.

Insights gained from these studies have led to other stimulating collaborations, with Professor Kevin D. Costa in the investigation of the role of proteoglycans in vascular wall mechanics, and with Professor David Elad in the area of oocyte mechanics.

To promote greater dissemination of these theoretical advances in the modeling of biological tissues, Prof. Ateshian has established a close collaboration with Professor Jeffrey A. Weiss of the University of Utah. In an effort involving several members of Columbia's Musculoskeletal Biomechanics Laboratory and Utah's Musculoskeletal Research Laboratories, these investigators are developing a free, open source, finite element program to model mechanics and transport in tissues and cells.